Ammonium-nitrate explosive.



lea s UNITED. STATES PATENT, OFFICE.

FIN SPARRE, OE I/VILMINGTON, DELAWARE, ASSIGNOR TO THE E. I. DU PON T DENEMOURS POWDER COMPANY, OF WILMINGTON, DELAI/VARE, A COR- PORATION OFNEW JERSEY.

AMMONiUM-NITRATE EX PLOSIVE.

Specification of Letters Patent.

Patented April 16, 1307.

Original application filed Dctober 24,1905, Serial No. 284,152. Dividedand this application filed May 31,1906, Serial No. 319,491.

To all whont it may concern:

Be it known that I, FIN SPARRE, a subject of the King of Norway,residing at Wilmington, county of Newcastle andState of Delaware, haveinvented a new and useful Imfproveme'nt in Ammonium-NitrateExploexplosive and awaterproof composition "conslstmg of a liquid nitrocompound (in which preferably has been dissolved a solid' nitrocompound) in which is dissolved guncotton or other nitrated cellulose,the composition whcn mixed with the nitrate of ammonia ornitrate-of-ammonia explosive coating the particles of the latter and producing a new nitrate-of-ammonia explosive impervious to moisture.

The invention also consists in the process of making suchnon-hygroscopic.nitrateofammonia explosive.

It has been proposed to manufacture non hygroscopic nitrate-of-ammoniapowder by dissolving a solid body, such as rosin, in a volatile solvent,such as alcohol, then mixing the solution with the ingredients of thepowder, and then evaporating the solvent. It has also been proposed toadd to the powder waterproofing liquids, such as kerosene It has alsobeen proposed to mix nitrate of ammonia or nitrate-of-ammonia powderwith solid nitro compounds, such as dinitrobenzol ormononitronaphthalene, and heating the mixture to a temperature at whichthe compounds will melt and then permitting the powder to cool, therebyproducing supposedly a powder whose particles were provided with awaterproof coat ing. These attempts, however, have not been. successful.There has either been no reduction of the hygroscopicity or it has beentoo slight to be of practical value.

Additions of small amounts of the li uids mentioned produce noappreciable bene cial results. Addition of larger amounts oftheseliquids not only fails to reduce the hygroscoplcity to any practicalextent, but it is lmpracti'cable to add large amounts, as they exuderapidly and spoil the explosive.

Moreover, such liquids are easily washed out by water, and thus are ofno practical use so far as waterproof'qualities are concerned. So far asnitroglycerin is concerned its ad.- dition in large enough quantities tobe appreciably eflicient to reduce hygroscopicity robs the powder of thevery qualities that commend it to usethat is, the powder is no longerfumeless, it freezes at a relatively high temperature, and it is lesssafe.

The failure of melted solid nitro compounds I to act efficiently isdoubtless due tQ tlIB-TTtOlT TO' 'T that these compounds crystallize,and therefore coat the particles of powder imperfectly.

and unevenly, and are brittle and porous at lower temperature.

It is essential in'order to obtain non-hygroscoplcity and waterproofingthat the hi trate of ammonia or nitrate-of-ammonia powder should becoated with or absorb a material that is amorphous, viscous, insolublein water, and waterproof and also combustible, non-freezing, stable,safe, and practically non-volatile at high or low temperature. Thismaterial I obtain, as before stated, by dissolving guncotton in a liquidnitro compound in which, preferably, has previously been dissolved asolid nitro compound. As'

examples of liquid nitro compounds that may be used may be specifiedmononitrobenzol and mononitrotoluol. As examples of solid nitrocompounds that may be used may be' specified idinit obenzoldinitrotoluol, and

'trinitro toluol, The guncotton used may be higher nitro compound isthatthe mixture contains more oxygen than if a mononitro compound onlyis present.

My preferred waterproof composition is as follows: mononitrotoluol,eighty per cent; trinitrotoluol, ten per cent; guncotton, ten per cent.The liquid nitro compound may, however, vary from sixty per cent. toninetynine per cent. The solid nitro compound should not exceedtwenty-five per cent, as a larger proportion produces crystallization.It may be omitted altogether, but with less completely satisfactoryresults, for the reasons above stated. The guncotton may vary from oneper cent. to fifteen per cent. Its addition is essential, as otherwisethe solution would be too thin. The guncotton is gelatinized, andtherefore perfectly safe.

The solution maybe prepare d cold or warm, application of heat not beingnecessary.

As examples of known nitrate-of-ammonia powders to which the abovewaterproof composition is applicable may be mentioned the following:nitrate of ammonia, eighty-five per cent; aluminium, fifteen per cent,also, nitrate of ammonia, seventy-eight per cent; ferrosilicon, twelveper cent; ungelatinized nitrocellulose, ten per cent., also, nitrate ofammonia, eighty-eight per cent. trinitrotoluol, six per cent;trinitronaphthalene, six per cent.

To apply the composition, the previouslyprepared powder is mixedtherewith in an ordinary mixing apparatus with or without application ofheat. The following proportions are preferable: nitrate of ammoniapowder, eighty-five per. cent. waterproof composition, fifteen per cent.

The proportion of the composition may vary from five per cent. to thirtyper cent.

In addition to the composition a quantity of nitrate of ammonia may beadded to the previously-prepared powderfor example, nitratepf-annnoniapowder, seventy-five per cent.; nitrate of ammonia, five per cent.;waterproof composition, twenty per cent.

Instead of adding the composition to a nitrate-of-ammonia powder it maybe added to nitrate of ammonia alone, thus producing a nitrate ofammonia powder of non hygroscopic propertiesfor example, nitrate ofammonia, eighty-two per cent; waterproof composition, eighteen per cent.

Another example of such powder is as follows: nitrate of ammonia,seventy-five per cent. waterproof composition, twenty per cent.nitroglycerin, five per cent.

The nitroglycerin may also first be dissolved in the composition and thenitrate of ammonia incorporated with this mixture.

An explosive may also be made of the fol lowing composition: nitrate ofammonia powder, seventy per cent; nitrate of ammo nia, seven andone-half per cent. nitroglycerin, seven and one-half per cent;waterproof composition, fifteen per cent. In this case the nitrate ofammonia may first be mixed with the powder and the nitroglycerindissolved in the composition and then these two mixtures incorporated,or all four may be incorporated together.

The following is an example of a waterproof composition containingnitroglycerin: mononitrobenzol, sixty-two per cent; trini trotoluol, tenper cent. nitroglycerin, twenty per cent. nitrocellulose, eight percent.

An explosive may also be made by adding nitrocellulose, as well as thecomposition, to nitrate of ammonia or a nitrate-of-ammonia owder.

Both the nitroglycerin and the nitrocellulose, if not gelatinized or insolution, act as sensitizing ingredients.

I have hercinbefore stated that the waterproof composition may live andthirty per cent. of the explosive, while in the examples the proportionsvary from fifteen to twenty per cent. Certain known nitrate-of-annnoniapowders to which the said waterproof composition is applicable have alsobeen set forth. As an example of a waterproofed nitrate-of-ammoniaexplosive embodying my invention, with the propertions of the variousingredients to the explosive as a whole, maybe mentioned the following:nitrate of ammonia, from fifty per cent. to eighty-five per cent,preferably sixty-live per cent. ferrosilicon, from five per cent. totwenty per cent. preferably ten per cent; ungelatinized nitrocelluslose,from five per cent. to twenty per cent, preferably ten per cent;mononitrobenzene, from five per cent. to thirty per cent, preferablytwelve per cent; trinitrotoluol, less than 7.5 per cent, preferably 1.5per cent; gel atinized nitrocellulose, less than 4.5 per cent,preferably 1.5 per cent.

This application is a division of an application filed by me October 24,1905, Serial No. 284,152.

Having now fully described my invention, what I claim, and desire toprotect by Letters Patent, is

1. A nitrate-of-amim nia explosive containing of nitrate of ammoniafifty to eightyiive per cent, of a liquid nitro compound three to thirtyper cen t., and of nitrocellulose dissolved in the liquid nitro compoundless than 4.5 per cent. substantially as described.

2. A nitrate-of-a1nmonia explosive containing of nitrate of ammoniafifty to eighty five per cent, of a liquid nitro compound three tothirty per cent, of a normally solid nitro eompoundless than 7.5 percent, and of nitrocellulose less than 4.5 per cent. substan tially asdescribed.

3. A non-hygroscopic nitrate-of-ammonia explosive containing anitratc-otammonia powder coated with a liquid nitro compound in whichhas been dissolved nitrocellulose, in substantially the describedproportions.

comprise between 4. A non-hygroscopic nitrate-of-ammonia explosivecontaining a nitrate-of-ammonia oWder coated with a liquid nitrocompound in which has been dissolved nitrocellulose, and a normallysolid nitro compound, in substan tially the described proportions.

5. A nitrate of ammonia explosive containing of nitrate of ammonia fiftyto eightyfive per cent, of mononitrotoluol three to thirty per cent, andof nitrocellulose dissolved in the liquid nitro compound less than 4.5per cent. substantially as described.

6. A nitrate of ammonia explosive containing of nitrate of ammonia fiftyto ei -htyfive per cent., mononitrotoluol three to thirty per cent.trinitrotoluol less than 7.5 per cent., and of nitrocellulose less than4.5 per cent.

substantially as described.

7. A non-hygroscopic nitraLe-of-arnmonia explosive containing anitrate-of-ammonia powder coated with mononitrotolpol in which has beendissolved nit fbcelliilbsfe in substantially the described prfipditidiis;

8. A. non-hygroscoplc nitrate-of-ammonia explosive containing an1trate-of-an1monra powder coated W1th mononitrotoluol in Which

